1. Field of the Invention
The present invention relates to a device for protecting a knuckle joint, which is for instance an element of the front steering or the suspension of a vehicle.
In the domain of automotive engineering, this type of knuckle joint, also called knuckle, is mounted on the ball joint pin of the suspension arm or on the ball joint pin of the steering rack. In both cases, the knuckle is very close to the brake disc, which is a significant heat source. For instance, the brake disc of a loaded utility vehicle can reach a temperature of up to 700° C.
A knuckle comprises mainly a knuckle articulation which is crimped to create the articulation and a boot in elastomeric rubber enveloping the assembly to protect it against dust.
The disadvantage of this type of knuckle is that the material used for the boot is very sensitive to high temperature and the proximity of the brake disc causes great damage to this boot.
In view of this, it is essential to protect the knuckle joint against high temperature. In current practice, this problem is solved by using a large plate installed between the brake disc and the knuckle in order to protect a large surface of the knuckle. However, this solution remains costly in terms of material to be supplied.
2. Description of the Related Art
Document EP0890500 discloses a protection device for the knuckle joint of a vehicle comprising an annular flange mounted on the knuckle, a heat screen which extends in height perpendicularly to the flange and in width along the annular periphery of the flange. Flange and screen are formed in one piece in a deep draw stamping operation starting from sheet metal. This operation is most often performed in several passes, in other words in several stamping operations. The process is not only long but also costly in energy, handling and stamping tooling.